import type { PropType } from 'vue';
import { defineComponent, ref, watch, onMounted, nextTick, unref, computed, CSSProperties } from 'vue';
import SvgIcon from './SvgIcon';
import '@purge-icons/generated';
import Iconify from '@iconify/iconify';
import { isString } from '/@/utils/is';
import { propTypes } from '/@/utils/propTypes';
import './Icon.less';

const SVG_END_WITH_FLAG = '|svg';
export default defineComponent({
  name: 'Icon',
  props: {
    // icon name
    icon: {
      type: String as PropType<string>,
      required: true,
    },
    // icon color
    color: {
      type: String as PropType<string>,
      required: false,
    },
    // icon size
    size: {
      type: [String, Number] as PropType<string | number>,
      default: 16,
    },
    spin: propTypes.bool.def(false),
    prefix: propTypes.string.def(''),
  },
  setup(props, { attrs }) {
    const elRef = ref<ElRef>(null);

    const isSvgIcon = computed(() => props.icon?.endsWith(SVG_END_WITH_FLAG));
    const getSvgIcon = computed(() => props.icon.replace(SVG_END_WITH_FLAG, ''));
    const getIconRef = computed(() => `${props.prefix ? props.prefix + ':' : ''}${props.icon}`);

    const update = async () => {
      if (unref(isSvgIcon)) return;

      const el = unref(elRef);
      if (!el) return;

      await nextTick();
      const icon = unref(getIconRef);
      if (!icon) return;

      const svg = Iconify.renderSVG(icon, {});
      if (svg) {
        el.textContent = '';
        el.appendChild(svg);
      } else {
        const span = document.createElement('span');
        span.className = 'iconify';
        span.dataset.icon = icon;
        el.textContent = '';
        el.appendChild(span);
      }
    };

    const getWrapStyle = computed((): CSSProperties => {
      const { size, color } = props;
      let fs = size;
      if (isString(size)) {
        fs = parseInt(size, 10);
      }

      return {
        fontSize: `${fs}px`,
        color: color,
        display: 'inline-flex',
      };
    });

    watch(() => props.icon, update, { flush: 'post' });

    onMounted(update);

    const getIconCom = (): VueNode => {
      if (isSvgIcon.value) {
        return (
          <>
            <SvgIcon size={props.size} name={getSvgIcon.value} class={[[attrs.class, 'anticon']]} spin={props.spin} />
          </>
        );
      }
      return (
        <>
          <span
            ref={elRef}
            class={[attrs.class, 'app-iconify anticon', props.spin && 'app-iconify-spin']}
            style={getWrapStyle.value}
          />
        </>
      );
    };

    return () => <>{getIconCom()}</>;
  },
});
